Blunt point needles

Abstract: Blunt tip surgical needles which significantly reduce the probability of skin penetration of the gloved hand of an operator are disclosed. In one embodiment, the blunt tip needle includes a tip portion which terminates in a bulbous blunt tip. In another embodiment, the needle tip portion includes a ball socket and a ball rotatably disposed therein.

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to surgical needles and, more particularly, to blunt tip surgical needles wherein the needle has a ball tip that can roll on a surface, to decrease potential skin penetration of the gloved hand of an operator. 2. Description of the Prior Art Everyone today is well aware of the severity of contracting Human Immunodeficiency Virus (HIV) and Acquired Immune Deficiency Syndrome (AIDS). The members of professions that must deal on a daily basis with the risk of coming in contact with people that do or may have HIV or AIDS are acutely aware of the severity. Members of the medical profession, especially surgeons, are in an extremely high risk position when performing operations. The knowledge that infectious diseases such as the AIDS virus can spread by an accidentally inflicted needle stick from a contaminated needle administered to the person having AIDS is the cause for much concern for the profession. These professionals are therefore taking every precaution to reduce the risks. For example, the use of double gloving, blunt tipped needles and gloves thickened at the fingers are known to reduce the rate of glove puncture. In addition, the use of forceps designed to grip both the tissue and needle more effectively and the use of staples for skin closure are also known to reduce the incidence of glove puncture. A blunt-tipped stylet has been previously described (GB-A-2064963), to reduce perforation of the transvenous pacing lead through which it is threaded. The stylet tapers from the handle to a tip at which a ball is affixed, with a diameter substantially equal to that of the stylet at its widest point. There have also been developments in the area of surgical needle tip design. For example, U.S. Patent 4,828,547 to Sahi et al. discloses a needle having a blunting member which is moveable from a retracted position to an extended position. In the retracted position, the blunting member does not interfere with the puncture tip of the needle. In the extended position, the blunting member extends beyond the puncture tip and therefore acts as a guard against accidental needle sticks. Further examples of shield or guard type assemblies for syringe needles are disclosed in U.S. Patent Nos. 4,883,469 to Glazier and 4,883,471 to Braginetz et al. The devices disclosed above are useful for hypodermic syringe needles which are disposed of after a single stick. This design would not be practical for use with surgical needles since such needles must make repeated sticks into the body. U.S. Patent No. 5,123,910 to McIntosh which discloses the features of the preamble of claim 1, defines a tapered needle tip having a circular cross-section and terminating in a blunt head. The blunt head has a part spherical or other curved shape with no sharp edge surfaces. However, since the blunt tip cannot roll on a surface to be contacted, this needle still can penetrate the gloved hand of an operator. Thus, although this blunt tip needle is an improvement over a conventional sharp point needle, it does not significantly reduce the probability of skin penetration of a gloved hand. Thus, there is a need to develop an improved surgical needle for use in suturing non-cutaneous and friable soft tissues of the body while at the same time significantly reducing the probability of skin penetration of the gloved hand of an operator. SUMMARY OF THE INVENTION The present invention as defined in claim 1, is directed to blunt tip surgical needles which significantly reduce the probability of skin penetration of the gloved hand of an operator thereby decreasing potential transmission of all infectious agents. According to the present invention, the needle tip portion includes a ball socket at its distal end for the rotable retention of a ball and a ball rotatably retained within the socket. In one embodiment of the invention the bottom of the ball socket includes a concave shaped ball seat. In an alternative embodiment, the ball socket includes a circumferentially inwardly inclined support surface disposed between first and second bores. In this embodiment, the ball rotatably contacts an upper rim of the first bore, a lower perimeter of the support surface and an upper rim of the second bore. In both of the embodiments, the ball makes the initial contact with the surface of the tissue to be penetrated. When the ball contacts the surface of a plastic glove, the ball will initially roll on the surface and not penetrate thereby allowing the surgeon to quickly withdraw the needle without penetrating through the glove and into the skin. Thus, the provision of the ball at the needle tip improves upon the prior art blunt tip needles in that the present needle is less likely to penetrate the glove and skin of the user. On the other hand the ball will not roll as freely when in contact with the tissue and can penetrate the tissue with the proper force applied to perform the suturing function. Thus, the rolling ball needle of the present invention provides protection against the unintentional stick of the gloved hand of an operator while not adversely effecting the surgeon's ability to suture tissue. As a result of having a rotatable ball tip, the needles of the present invention are a significant improvement over conventional sharp point needles and prior art blunt tip needles. The improved blunt tip surgical needles of the present invention are suitable for use in suturing soft-non-cutaneous or friable body tissues, as well as other types of tissue, while providing increased protection against an unintended stick of the gloved hand of an operation. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of the tip portion of a surgical needle according to the present invention. FIG. 2 is a cross-sectional view of the tip portion of FIG. 1 without the rotatable ball. FIG. 3 is a cross-sectional view of the tip portion of another embodiment of a surgical needle of the present invention. DETAILED DESCRIPTION OF THE INVENTION The diameter of the main body of the needles can be in the range of about 0.5 mm (0.020") to 1.3 mm (0.050"). The needles are rigidly formed of a suitable material such as surgical grade steel, plastic material and/or combinations of steel and plastic. Referring to FIG. 1, there is shown another embodiment of a surgical needle 40 according to the present invention. The needle tip portion 42 can have a circular cross-sectional shape which decreases progressively from its proximal end 44 to its distal end 46. The tip portion 42 terminates in a blunt tip 48. The blunt tip 48 comprises a ball socket 50 adapted to hold a freely rotatable ball 52. The ball socket 50 at its outer tip has a ball clasping bore 54 and a contiguous conical shaped ball seat 56 as shown in FIG. 2. The ball 52 is assembled in place by fitting it through the open end of the bore 54 and onto the ball seat 56 and crimping the rim of the bore 54 at its extremity so that it clasps the ball 52 and prevents it from dropping out. The ball 52 can have a diameter ranging from about 0.13 mm (0.005") to 1.5 mm (0.060"). FIG. 3 shows a further embodiment of a surgical needle 60 of the present invention. The ball socket 62 is adapted to retain the freely rotatable ball 52. In this embodiment, the ball socket 62 includes a circumferentially inwardly inclined support surface 64 disposed between and contiguous with a first bore 66 and a second bore 68. The ball 52 is in contact with an upper rim of the first bore, a lower perimeter of surface 64 and an upper rim of the second bore 68. A contiguous conical shaped portion 70 extends from a lower part of the second bore 68. The first bore 66 is a ball clasping bore and is crimped at its rim to rotatably contain ball 52 and prevent it from dropping out. It should be understood by those skilled in the art of the present invention that the shape and configuration of the ball holder, socket and ball seat are not critical to the present invention and can therefore assume any configuration which allows the ball 52 to be freely rotatable. For example, in addition to the embodiments described above, ball seat 56 can have an inclined concave surface or an open spherical surface. The curved surface of ball 52 of the needles of the present invention significantly decrease the probability of skin penetration of the gloved hand of an operator as compared to conventional sharp point needles and prior art blunt tip needles. In addition, the needles 40 and 60 provide additional protection against an unintentional stick of the gloved hand of an operator in that when the ball 52 contacts the surface of a latex glove, the ball will roll on the surface without penetrating it. This allows the surgeon to quickly withdraw the needle without penetrating through the glove and into the skin. The needles 40 and 60 have the further advantage that the ball 52 can be made of a hard material such as carbide while the needle body 42 can be made of any one of the steel materials described above with regard to needles 10 and 30. This will provide sufficient structural integrity to the ball 52 to effectively penetrate non-cutaneous tissue without the ball being damaged or otherwise deformed. The needles of the present invention are suitable for use in suturing the liver, kidney, heart, muscle and fascia, adipose pericostal tissue and other non-cutaneous soft tissues of the body, as well as other types of tissue, while simultaneously decreasing the probability of skin penetration of the gloved hand of an operator and operating personnel such as surgeons, surgeons' assistants, scrube and circulating nurses. While the invention has been particularly shown and described with respect to illustrative and preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details may be made therein without departing from the scope of the invention which should be limited only by the appended claims.

Claims: A surgical needle (40) comprising a tip portion (32) having a proximal (44) and a distal end (46) characterised in that the said distal end (46) has a ball socket (50) for the rotatable retention of a ball, and a ball (52) rotatably retained within said ball socket. The surgical needle (40) according to claim 1, wherein the ball socket (50) includes a first bore (54) at an upper portion of the ball socket. The surgical needle (40) according to claim 2, wherein said ball socket (50) further includes a concave shaped ball seat (56) at a bottom of the ball socket and contiguous with said first bore (54). The surgical needle (40) according to claim 3, wherein the ball seat (56) has a shape selected from the group consisting of conical and spherical. The surgical needle (40) according to claim 2, wherein said ball socket (62) further includes a second bore (68) and a circumferentially inwardly inclined support surface (64) disposed between and contiguous with the first (66) and second (68) bores. The surgical needle (40) according to claim 5, further including a conical shaped lower surface (70) extending from a lower perimeter of said second bore (68). The surgical needle (40) according to any preceding claim, further including a suture mounting portion having a hole to which a suture is to be attached, and a body portion which is disposed between and contiguous with said suture mounting portion and said tip portion. The surgical needle (40) according to claim 7, wherein said body portion has a generally uniform cross-sectional area throughout an entire length thereof. The surgical needle (40) according to claim 7 or claim 8 wherein said cross-sectional area of said body portion has a shape selected from the group consisting of circular, square, rectangular, triangular and flat pressed circular. The surgical needle (40) according to any preceding claim, wherein said needle has an overall curved shape with a constant radius of curvature.

Inventors: MCGREGOR WALTER, SHCHERVINSKY SEMYON, MCGREGOR, WALTER, SHCHERVINSKY, SEMYON
Applicants: ETHICON INC, ETHICON, INC.
Application year: 1994
Main classification: A61B17
IPC codes: A61M5, A61B17